The instrument requested in this application is a configuration of the Becton Dickinson (BD) LSR II Flow Cytometer. This configuration of the BD LSR II has five lasers;(Blue laser/Red laser/Yellow-Green laser/Violet laser/UV laser) and the BD High Throughput Sampler (HTS). Nine qualified users have been identified with specific needs for advanced flow cytometry. All nine users are situated in two off-campus buildings which while close to each other are a significant distance from the on-campus Flow Cytometry Core which houses flow cytometers that have some of the required technology but are oversubscribed and often have to be accessed after normal working hours when technical support is not available. To service the growing need for analytical flow cytometry by investigators housed outside the main campus the on-campus Flow Cytometry Core has established two satellite facilities. The satellite flow facility that is part of the Department of Molecular and Experimental Medicine (MEM) is ideally situated as the site for the only off-campus LSR II cytometer due to the presence of designated space, technical support and a significant population of investigators who use flow cytometry in their research. This satellite facility houses two FACSCaliburs that are eight years old and use technology that is unable to support the growing need for experiments requiring greater than 4 colors. In addition they are incapable of performing the specialized tasks required by multiple members of the User Group. Access to a BD LSR II by off-campus investigators would provide much needed instrumentation and greatly facilitate NIH funded studies in the areas of influenza, asthma, sepsis, autoimmunity, HIV/AIDS, cancer, aging, stem cells, macromolecular imaging, cytoskeleton and cell shape, and protein-carbohydrate interactions. PUBLIC HEALTH RELEVANCE: The Becton Dickinson LSR II is a versatile and powerful flow cytometer capable of multi-color, multiparameter analysis. Such an instrument is an invaluable tool in identifying the numerous cell populations and their subsets that contribute to many diseases. The availability of such an instrument to investigators in the Department of Molecular and Experimental Medicine of the Scripps Research Institute will greatly facilitate cutting-edge research in the areas of influenza, asthma, sepsis, autoimmunity, HIV/AIDS,cancer, aging, stem cells, macromolecular imaging, cytoskeleton and cell shape, and proteincarbohydrate interactions.